I inherited an older installation of WPMU 2.6 and now want to upgrade to WP multisite. My plan was to incrementally upgrade the WPMU versions to 2.9 and then jump over to the merged core. But I see now that the downloads of WPMU have disappeared from this page: http://codex.wordpress.org/Upgrading_WPMU#WordPress_MU_2.7.1_Archive_Link.
The links are there, but they do not work.
So, does anyone know where I can find older WPMU installs? Or does anyone know how to upgrade from WPMU 2.6 to the current WP? It appears that 2.7 was substantailly different enough that I should at least step up to that version before getting current.